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On Cuticular Compressions of Glyptostrobus europaeus (Taxodiaceae) from Kaydagul Formation (Lower Miocene) of the Central Kazakhstan$V. L. Komarov Botanical Institute! Russian Academy of Sciences,St Petersburg 19737 被引量:3
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作者 Sergei Vasilyevich VICKULIN 马清温 +1 位作者 Sergey Glebovich ZHILIN 李承森 《Acta Botanica Sinica》 CSCD 2003年第6期673-680,共8页
Numerous leaf compressions of Glyptostrobus europaeus (Brongn.) Ung. (Taxodiaceae) are found in Aquitanian (Lower Miocene) lignified clay localities Bolattam and Akzhar in the Southern Turgay, on the right bank of the... Numerous leaf compressions of Glyptostrobus europaeus (Brongn.) Ung. (Taxodiaceae) are found in Aquitanian (Lower Miocene) lignified clay localities Bolattam and Akzhar in the Southern Turgay, on the right bank of the Dulygaly-Zhilanshik river (Central Kazakhstan). The finely preserved lignified compression remains of leafy shoots make micro-morphological investigation feasible. Comparative studies of the epidermal features both living G. pensilis C. Koch and a new finding of G. europaeus from Early Miocene of Kazakhstan and illustrate their certain difference. The cuticular organization and epidermal features of fossil leaves, which have been compared with these of 'the nearest living relative', G. pensilis, were studied by scanning electron microscopy (SEM) and light microscopy (LM). The fossil leaves of G. europaeus from Kazakhstan are distinguished by stronger, than in living species, G. pensilis, developed 'micro-papillae' ('Kristallucken'), visible in SEM as ring-like structures left on the outer surface of cuticle in both nonstomatal and stomatal zones. 展开更多
关键词 CONIFERS TAXODIACEAE STOMATA leaf cuticle Lower Miocene
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Uncovering genes essential in domestication and breeding of sugar beet
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作者 Amar Singh Dhiman Nazgol Emrani +2 位作者 Eva Holtgrewe-Stukenbrock Mark Varrelmann Christian Jung 《The Crop Journal》 2025年第4期1224-1233,共10页
The genus Beta encompasses economically important root crops such as sugar and table beet.A Beta diversity set including the wild relative B.vulgaris ssp.maritima was grown in the field,and a large phenotypic diversit... The genus Beta encompasses economically important root crops such as sugar and table beet.A Beta diversity set including the wild relative B.vulgaris ssp.maritima was grown in the field,and a large phenotypic diversity was observed.The genomes of 290 accessions were sequenced,and more than 10 million high-quality SNPs were employed to study genetic diversity.A genome-wide association study was performed,and marker-trait associations were found for nine phenotypic traits.The candidate gene within the M locus controlling monogermity on chromosome 4 was previously unknown.The most significant association for monogermity was identified at the end of chromosome 4.Within this region,a non-synonymous mutation within the zinc-finger domain of the WIP2 gene co-segregated with monogermity.This gene plays a regulatory role in AGL8/FUL in Arabidopsis.Intriguingly,commercial hybrids are in a heterozygous state at this position.Thus,the long-sought gene for monogermity was identified in this study.Red and yellow pigmentation due to betalain accumulation in shoots and roots is an important characteristic of table and leaf beets.The strongest associations were found upstream or downstream of two genes encoding Cytochrome P450 and anthocyanin MYB-like transcription factor proteins involved in betalain biosynthesis.Significant associations for Cercospora leaf spot resistance were identified on chromosomes 1,2,7,and 9.The associated regions harbor genes encoding proteins with leucinerich repeats and nucleotide binding sites whose homologs are major constituents of plant-pathogen defense. 展开更多
关键词 Beta vulgaris GWAS Population structure Mixed linear model Monogermity Bolting time Cercospora leaf spot
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Antibacterial,antibiofilm,and wound healing activities of Piper longum root in multidrug-resistant Staphylococcus aureus infected mice
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作者 Pooja Gaur Pashupatinath Shukla +1 位作者 Jitesh Yadav Ch.V.Rao 《Asian Pacific Journal of Tropical Biomedicine》 2025年第5期189-199,I0002-I0012,共22页
Objective:To explore the effect of a hydrogel of Piper longum(P.longum)root against biofilm-forming multidrug-resistant(MDR)Staphylococcus aureus(S.aureus)through in vitro,in silico,and in vivo studies.Methods:We isol... Objective:To explore the effect of a hydrogel of Piper longum(P.longum)root against biofilm-forming multidrug-resistant(MDR)Staphylococcus aureus(S.aureus)through in vitro,in silico,and in vivo studies.Methods:We isolated the P.longum root ethanolic extract and the compounds using p-HPLC.In vitro antibacterial and antibiofilm activities of P.longum root extract and isolated alkamide compounds against biofilm-forming MDR S.aureus(ATCC 33591)were assessed using agar diffusion and broth microdilution methods,respectively.In silico investigations were conducted to investigate the interaction of alkamide compounds with three target proteins glycogen synthase kinase 3β(GSK3β),matrix metalloproteinases-8(MMP-8),and inducible nitric oxide synthase(iNOS).In addition,the wound healing effect of P.longum root extract 2%and 5%(w/v)-containing hydrogels was determined in mice.Results:The ethanolic root extract of P.longum and its compounds exhibited in vitro antibacterial activity with minimum inhibitory concentrations between 50µg/mL and 700µg/mL,as well as significantly reduced biofilm formation.Piperdardine isolated from P.longum root extract had the best molecular docking score(-9.7,-9.8,and-9.2 kcal/mol)with target proteins GSK3β,MMP-8,and iNOS.In vivo studies showed that P.longum hydrogels significantly lowered the number of colony-forming units(P<0.05).The P.longum 5%(w/v)hydrogel-treated group showed enhanced wound healing activity,achieving a wound contraction rate of 99.34%on day 14.Furthermore,histopathological analysis confirmed increased re-epithelialization and reduced inflammation in mice treated with P.longum 5%(w/v)hydrogel.Conclusions:P.longum root extract has pharmacological potential as an antibacterial and wound-healing agent,and further research is required to confirm its efficacy and clinical application. 展开更多
关键词 Piper longum L. Wound healing ANTIBIOFILM ANTIBACTERIAL MDR Staphylococcus aureus In silico docking
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Evaluation of transgenic cotton lines expressing an insecticidal fern protein against whitefly,Bemisia tabaci(Gennadius)
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作者 KUMAR Rishi NAGRARE V.S. +14 位作者 SHAH Vivek SINGH Satnam PANDHER Suneet SINGH Satpal VERMA S.K. PAUL Debashis RATHORE Pankaj SHUKLA Anoop Kumar SINGH Mithlesh Kumar SAURABH Sharad KUMAR Harish KAUR Rupinderjeet SINGH Pradhyumna Kumar WAGHMARE V.N. PRASAD Y.G. 《Journal of Cotton Research》 2025年第2期163-177,共15页
Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with des... Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding. 展开更多
关键词 EVALUATION Fern protein Transgenic cotton lines WHITEFLY
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Safeguarding Andaman flora:New plant biorepository strengthens global genome conservation
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作者 Anurag Dhyani K.K.Sabu +3 位作者 M.P.Geethakumary M.A.Jabbar S.Suresh Morgan R.Gostel 《Plant Diversity》 2025年第6期995-997,共3页
The Andaman Islands,part of the Indo-Burma biodiversity hotspot,holds unique florawith many endemic and threatened species.However,this fragile diversity is under increasing pressure from infrastructure expansion,clim... The Andaman Islands,part of the Indo-Burma biodiversity hotspot,holds unique florawith many endemic and threatened species.However,this fragile diversity is under increasing pressure from infrastructure expansion,climate change and habitat fragmentation.The recently announced Great Nicobar Island Development project by the Government of India,which includes an international transhipment terminal,airport,township and power plant,if implemented,would cause major habitat loss and fragmentation,possibly leading to species extinctions. 展开更多
关键词 Andaman flora endemic threatened specieshoweverthis global genome conservation great nicobar island development project plant biorepository infrastructure expansion Indo Burma biodiversity hotspot habitat fragmentationthe
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Expression of Recombinant Tryptophan Decarboxylase in Different Subcellular Compartments in Tobacco Plant 被引量:2
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作者 王淼 李秋荣 +1 位作者 Stefano Di FIORE Rainer FISCHER 《Acta Botanica Sinica》 CSCD 2002年第3期314-317,共4页
The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicoti... The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality. 展开更多
关键词 tryptophan decarboxylase alkaloids biosynthetic pathway Nicotiana tabacum subcellular compartment
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水稻120kDa光敏色素的提纯 被引量:1
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作者 童哲 R.Schendel +1 位作者 W.Rdiger 宋国清 《Acta Botanica Sinica》 CSCD 1989年第12期897-902,共6页
采用改进的 Grimm 等方法,从晚粳“农垦58”水稻(Oryza sativa L.subsp.japonica,var.nongken 58)6天龄黄化苗中提取光敏色素。经液氮深冻的胚芽鞘在含有乙二醇和苯甲基磺酰氟化物等、pH 为8.45的 Tris 缓冲液中匀浆。对聚乙烯亚胺沉淀... 采用改进的 Grimm 等方法,从晚粳“农垦58”水稻(Oryza sativa L.subsp.japonica,var.nongken 58)6天龄黄化苗中提取光敏色素。经液氮深冻的胚芽鞘在含有乙二醇和苯甲基磺酰氟化物等、pH 为8.45的 Tris 缓冲液中匀浆。对聚乙烯亚胺沉淀后的提取液照射红光,经硫酸铵盐析后、通过羟基磷灰石柱层析梯度洗脱。合并的含有光敏色素的洗脱液再经硫酸铵盐析和三次不同体积、不同浓度的磷酸缓冲液洗涤。最后溶于 HEPES 缓冲液的天然光敏色素(120kDa)经 SDS-PAG 电泳检测为一条带,并具有经典的纯净光敏色素的吸收光谱,产率达12%。 展开更多
关键词 水稻 光敏色素 提纯
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Expression of Strictosidine Synthase in Selected Subcellular Compartments of Tobacco Plant
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作者 王淼 李秋荣 +1 位作者 Stefano Di FIORE Rainer FISCHER 《Acta Botanica Sinica》 CSCD 2002年第5期579-582,共4页
Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to... Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis. 展开更多
关键词 Nicotiana tabacum strictosidine synthase subcellular compartment EXPRESSION
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新疆植物区系新资料(英文) 被引量:6
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作者 Dmitry A. GERMAN Alexander I. SHMAKOV +5 位作者 张宪春 陈文俐 Sergey V. SMIRNOV 谢磊 Rudolph V. KAMELIN 王健 《植物分类学报》 CSCD 北大核心 2006年第5期598-603,共6页
报道了采自新疆阿尔泰山地区的1个中国新记录属假糖芥属Rhammatophyllum O. E. Schulz, 6个中国新记录种——渐尖岩蕨Woodsia acuminata (Fomin) Sipl.、短命繁缕Stellaria alsinoides Boiss. & Buhse、假糖芥Rh. erysimoides (Kar.... 报道了采自新疆阿尔泰山地区的1个中国新记录属假糖芥属Rhammatophyllum O. E. Schulz, 6个中国新记录种——渐尖岩蕨Woodsia acuminata (Fomin) Sipl.、短命繁缕Stellaria alsinoides Boiss. & Buhse、假糖芥Rh. erysimoides (Kar. & Kir.) Al-Shehbaz & O. Appel、克氏鹤虱Lappula krylovii Ovczinnikova, A. I. Pjak & A. L. Ebel、肝色柳穿鱼Linaria hepatica Bunge和佐氏新缬草Valerianella szovitsiana Fisch. & Mey.。 展开更多
关键词 假糖芥属 渐尖岩蕨 短命繁缕 假糖芥 克氏鹤虱 肝色柳穿鱼 佐氏新缬草 新记录 新疆 中国
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藻红蓝蛋白α-亚基脱辅基蛋白与藻蓝胆素的重组 被引量:2
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作者 王鲁 周明 +3 位作者 邓明刚 赵开弘 STORF Max SCHEER Hugo 《武汉植物学研究》 CAS CSCD 2002年第1期38-42,共5页
利用在大肠杆菌中表达的藻红蓝蛋白 α-亚基脱辅基蛋白与藻蓝胆素 PCB重组 ,吸收光谱、荧光光谱和高效可逆光化学性质分析表明 ,藻红蓝蛋白 α-亚基脱辅基蛋白与藻蓝胆素直接重组 ,生成的胆素蛋白中辅基色素仍为藻蓝胆素 ;而藻红蓝蛋白 ... 利用在大肠杆菌中表达的藻红蓝蛋白 α-亚基脱辅基蛋白与藻蓝胆素 PCB重组 ,吸收光谱、荧光光谱和高效可逆光化学性质分析表明 ,藻红蓝蛋白 α-亚基脱辅基蛋白与藻蓝胆素直接重组 ,生成的胆素蛋白中辅基色素仍为藻蓝胆素 ;而藻红蓝蛋白 α-亚基脱辅基蛋白与藻蓝胆素在藻红蓝蛋白 α-亚基重组酶 (pec E和 pec F基因的表达产物 )催化下重组 ,生成的胆素蛋白中辅基色素转变为藻紫胆素 ,并具有高效可逆光化学特性。 展开更多
关键词 藻红蓝蛋白α-亚基 重组 高效可逆光化学特性 脱辅基蛋白 藻蓝胆素
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华南地区新生代木乃伊化木化石研究进展 被引量:2
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作者 黄路亮 Alexei Asafievich Oskolski +1 位作者 全成 金建华 《古生物学报》 CAS CSCD 北大核心 2023年第4期546-566,共21页
中国木化石资源虽然很丰富,但研究程度相比叶片化石要低得多,且主要集中在中国北部和西南地区,研究领域大多局限于分类学方面,而木化石分析与古气候、古生态等领域的交叉和系统研究还很少。大多数情况下木化石的保存方式都为石化或矿化... 中国木化石资源虽然很丰富,但研究程度相比叶片化石要低得多,且主要集中在中国北部和西南地区,研究领域大多局限于分类学方面,而木化石分析与古气候、古生态等领域的交叉和系统研究还很少。大多数情况下木化石的保存方式都为石化或矿化保存,而木乃伊化保存的木化石则非常罕见。木乃伊化保存的化石在植物分类、系统演化及古气候研究等方面具有独特而重要的价值。近年来,本团队在华南地区发现大量木乃伊化保存的新生代木化石,它们分别产自广西南宁盆地晚渐新世邕宁组、广西桂平盆地中新世二子塘组以及广东茂名盆地晚更新世地层中。本文总结了这些木乃伊化保存的木化石的研究进展,包括多样性组成、古植被、古气候及古生态等特征,并对木兰属、蒲桃属和枫香属的植物地理史进行了讨论。综合分析植物群组成特征和木材生长轮以及木化石中具有气候指示意义的解剖结构特征,推测广西南宁盆地晚渐新世时期生长着常绿(少数落叶)阔叶林,为温暖湿润的亚热带季节性气候;广西桂平盆地中新世时期生长着常绿—落叶、阔叶—针叶混交林(阔叶为主),为温暖湿润的亚热带气候;广东茂名盆地晚更新世生长着常绿—落叶、阔叶—针叶混交林,为温暖湿润的亚热带至热带季风气候。这是中国低纬度地区首次系统研究木乃伊化保存的木化石,为新生代植物群的系统演化和古环境分析等提供了重要的木化石依据。 展开更多
关键词 古植被 古气候 古生态 华南 木乃伊化木化石 新生代
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拟南芥中一个与ABA信号途径相关未知蛋白质的研究初报
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作者 秦晓克 黄跃 +4 位作者 杨笑瑒 蒋彦 李旭锋 Erwin Grill 杨毅 《中国农业科技导报》 CAS CSCD 2007年第3期112-117,共6页
利用酵母双杂交系统在拟南芥cDNA文库中筛选出1个与ABI2有相互作用的未知蛋白质(AC)。在酵母系统中的进一步研究表明,AC与ABI1、ABI2有相互作用,其作用依赖于ABI1、ABI2的PP2C活性。在大肠杆菌中表达和纯化了与预测结果一致的AC蛋白质... 利用酵母双杂交系统在拟南芥cDNA文库中筛选出1个与ABI2有相互作用的未知蛋白质(AC)。在酵母系统中的进一步研究表明,AC与ABI1、ABI2有相互作用,其作用依赖于ABI1、ABI2的PP2C活性。在大肠杆菌中表达和纯化了与预测结果一致的AC蛋白质。构建了真核过量表达载体,转化拟南芥后筛选和鉴定出转基因AC植株。转基因植株的生理性状分析表明,AC基因的过量表达降低了植物对ABA敏感性。研究初步证明AC可能是脱落酸信号传导途径中的1个新信号分子。 展开更多
关键词 脱落酸信号传导 未知蛋白质AC 转基因拟南芥 酵母双杂交系统
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Identification of EST–SSRs and molecular diversity analysis in Mentha piperita 被引量:16
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作者 Birendra Kumar Umesh Kumar Hemant Kumar Yadav 《The Crop Journal》 SCIE CAS CSCD 2015年第4期335-342,共8页
EST sequences of Mentha piperita available in the public domain(NCBI) were exploited to develop SSR markers. A total of 1316 ESTs were assembled into 155 contigs and 653 singletons and of these, 110 sequences were fou... EST sequences of Mentha piperita available in the public domain(NCBI) were exploited to develop SSR markers. A total of 1316 ESTs were assembled into 155 contigs and 653 singletons and of these, 110 sequences were found to contain 130 SSRs, with a frequency of1 SSR/3.4 kb. Dinucleotide repeat SSRs were most frequent(72.3%) with the AG/CT(43.8%)repeat motif followed by AT/AT(16.2%). Primers were successfully designed for 68SSR-containing sequences(62.0%). The 68 primers amplified 13 accessions of M. piperita and 54 produced clear amplicons of the expected size. Of these 54, 33(61%) were found to be polymorphic among M. piperita accessions, showing from 2 to 4 alleles with an average of2.33 alleles/SSR, and the polymorphic information content(PIC) value varied between 0.13 and 0.51(average 0.25). All the amplified SSRs showed transferability among four different species of Mentha, with a highest in Mentha arvensis(87.0%) and minimum in Mentha citrata(37.0%). The newly developed SSRs markers were found to be useful for diversity analysis, as they successfully differentiated among species and accessions of Mentha. 展开更多
关键词 EST–SSRs GENETIC DIVERSITY MENTHA piperita POLYMORPHIC information content Transferability
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A Review on the Taxonomic,Evolutionary and Phytogeographic Studies of the Lotus Plant(Nelumbonaceae:Nelumbo) 被引量:7
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作者 LI Ya Popova SVETLANA +1 位作者 YAO Jianxin LI Chengsen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1252-1261,共10页
Nelumbo Adans. (Nelumbonaceae) is an important member of the early-diverging eudicots. It contains two extant species: N. nucifera Gaertn. (the Sacred lotus), distributed in Asia and Australia and N. lutea Willd.... Nelumbo Adans. (Nelumbonaceae) is an important member of the early-diverging eudicots. It contains two extant species: N. nucifera Gaertn. (the Sacred lotus), distributed in Asia and Australia and N. lutea Willd. (the American lotus), occurring in North America. This paper reviews the taxonomic, evolutionary and phytogeographic studies of the genus Nelumbo, and also raises scientific questions about it in further paleobotanic research. There are about 30 fossil species of Nelumbo established since the Early Cretaceous. Based on fossil studies, the ancestors of the extant N. nucifera and N. lutea are respectively considered to be N. protospeciosa from the Eocene to Miocene of Eurasia, and N. protolutea from the Eocene of North American. However, molecular systematic studies indicate that N. nucifera and N. lutea are probably split from a common ancestor during the Late Miocene to Early Pliocene, or even the Pleistocene, rather than separate relicts from extinct species on different continents. The characters of lotus stomatal development, seedling morphology as well as its flowering, pollination and fertilization in air reveal that it evolves from the land plants. Fossil data of Nelumbo indicates that the genus first occurs in mid-latitude area of Laurasia in the Early Cretaceous, then becomes widespread in North America and Eurasia and expands into Africa and South America during the Late Cretaceous; the genus probably colonizes the Indian Subcontinent from Asia during the Early Eocene after the collision of India and the Asian plates; the genus becomes extinct in Europe, but survives in Asia and North America during the Quaternary Ice Age, and later forms the present East Asia and North Australia-North America disjunctive distribution. 展开更多
关键词 TAXONOMY evolution phytogeography NELUMBO Nelumbonaceae
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Determination of flavonoids,polyphenols and antioxidant activity of Tephrosia purpurea:a seasonal study 被引量:4
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作者 Madan Mohan Pandey Sayyada Khatoon +1 位作者 Subha Rastogi Ajay Kumar Singh Rawat 《Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第6期447-455,共9页
OBJECTIVE: Tephrosia purpurea (Linn.) Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study investiga... OBJECTIVE: Tephrosia purpurea (Linn.) Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study investigations were carried out to determine the seasonal impact on the content of flavonoid glycosides and on antioxidant activities so as to identify the optimal time of harvesting. METHODS: The plant materials were collected in different seasons during 2013-2014. Air-dried, powdered plant materials were extracted with 95% ethanol and ethanol:water (1:1 ) by ultrasound-assisted extraction process. Their chemical composition in terms of total polyphenol and flavonoid contents (TPCs and TFCs) was determined using modified colorimetric Folin-Ciocalteu method and aluminum chloride colorimetric assay respectively. To determine the in vitro antioxidant activity, diphenyl-picryl hydrazyl (DPPH) radical-scavenging assay and total antioxidant capacity by phosphomolybdate antioxidant assay were carried out. High-performance liquid chromatography (HPLC)/photo-diode array (PDA) analysis was used to quantify the flavonoid glycosides in the samples collected in different seasons. Correlation studies were also carried out between antioxidant activities and TPCs. RESULTS: The highest TPC and TFC were found to be in the 95% ethanolic extract of the August sample and the lowest in the 50% hydro-alcoholic extract of the plant sample collected in winter season. It was observed that in both the assays used to determine the antioxidant activity, the 95% ethanolic extracts in all the seasons showed a higher activity than their respective 50% hydro- alcoholic extracts with an increase in activity as we go from cold to hot to rainy seasons. Based on correlation analysis, DPPH radical-scavenging activities as well as the spectrophotometrically measured phosphomolybdenum complex were also strongly correlated with TPC of the extracts, The most abundant flavonoid glycoside was quercetin-3-O-rhamnoglucoside in all the seasons. The content of all flavonoids was observed highest in the 95% ethanolic extract of the plant collected in August (TP-3). The 50% hydro-alcoholic extract of the plant collected in December (TP-6) showed the lowest amount of flavonoids and antioxidant activity. CONCLUSION: The findings of this study confirmed that the metabolism and production of flavonoids in T. purpurea are vigorously affected by seasonal factors. Significant differences were observed in the TPC, TFC and flavonoid glycoside composition in the 95% ethanolic as well as 50% hydro-alcoholic extracts of 7: purpurea collected in different seasons. Since the 95% ethanolic extract of the August sample (TP-3), which also happens to be its flowering season, exhibited the highest TPC, TFC and antioxidant activities in both DPPH and phosphomolybdate assays as well as contained the highest content of allflavonoids, it could be recommended as the optimal season of harvesting T. purpurea with respect to its pharmaceutically important constituents, i.e., flavonoids. 展开更多
关键词 Tephrosia chromatography high-performance liquid flavonoid glycosides seasonal variation antioxidant effect
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Antitumor effects of different Ganoderma lucidum spore powder in cell-and zebrafish-based bioassays 被引量:21
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作者 Yue-jiao Shi Hua-xian Zheng +4 位作者 Zhu-ping Hong Han-bo Wang Ying Wang Ming-yan Li Zhen-hao Li 《Journal of Integrative Medicine》 SCIE CAS CSCD 2021年第2期177-184,共8页
Objective:Ganoderma lucidum spore(GLS)is gaining recognition as a medicinal part of G.lucidum and has been reported to possess various pharmacological properties,such as antitumor activity.In this work,wall-broken GLS... Objective:Ganoderma lucidum spore(GLS)is gaining recognition as a medicinal part of G.lucidum and has been reported to possess various pharmacological properties,such as antitumor activity.In this work,wall-broken GLS powder(BGLSP)and wall-removed GLS powder(RGLSP),two kinds of GLS powder with different manufacturing techniques,were compared in terms of contents of active constituents and in vivo and in vitro antitumor effects.Methods:The ultraviolet and visible spectrophotometry method was used to determine the contents of polysaccharides and total triterpenoids in BGLSP and RGLSP.Seventeen individual triterpenoids were further quantified using ultra-high-performance liquid chromatography and quantitative analysis of multicomponents by single marker.The antitumor effects of BGLSP and RGLSP were evaluated using in vitro cell viability assay against human gastric carcinoma SGC-7901,lung carcinoma A549 and lymphoma Ramos and further validated by in vivo zebrafish xenograft models with transplanted SGC-7901,A549 and Ramos,Results:The results showed that the contents of polysaccharides,total triterpenoids and individual triterpenoids of RGLSP were significantly higher than those of BGLSP.Although both BGLSP and RGLSP inhibited the three tumor cell lines in vitro in a dose-dependent manner,the inhibitory effects of RGLSP were much better than those of BGLSP.In the in vivo zebra fish assay,RGLSP exhibited more potent inhibitory activities against tumors transpla nted into the zebra fish compared with BGLSP,and the inhibition rates of RGLSP reached approximately 78%,31%and 83%on SGC-7901,A549 and Ramos,respectively.Conclusion:The results indicated that the antitumor effects of GLS were positively correlated with the contents of the polysaccha rides and triterpenoids and demonstrated that the wall-removing manufacturing technique could significantly improve the levels of active constituents,and thereby enhance the antitumor activity. 展开更多
关键词 Ganoderma lucidum Tumor Cancer cell ZEBRAFISH Wall-broken Ganoderma lucidum spore powder Wall-removed Ganoderma lucidum spore powder
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Hepatoprotective effect of Solatium xanthocarpum fruit extract against CCl_4 induced acute liver toxicity in experimental animals 被引量:5
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作者 Ramesh K Gupta Talib Hussain +5 位作者 G.Panigrahi Avik Das Gireesh Narayan Singh K Sweety Md Faiyazuddin Chandana Venkateswara Rao 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第12期964-968,共5页
Objective:To investigate the hepatoprotective potential of Solonum xanthocarpum(Solanaceae) (S.xanthocarpum) in experimental rats to validate its traditional claim.Methods:50%ethanolic fruit extract of S.xanthocar... Objective:To investigate the hepatoprotective potential of Solonum xanthocarpum(Solanaceae) (S.xanthocarpum) in experimental rats to validate its traditional claim.Methods:50%ethanolic fruit extract of S.xanthocarpum(SXE,100.200 or 400 mg/kg hods weight) was administered daily for 14davs in experimental animals.Liver injury was induced chemically,by CCl<sub>4</sub> administration (1 mL/kg i.p.).The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase(AST),alanine aminotransferase(ALT).Serum alkaline phosphatise (SALP) and total bilirubin.Meanwhile,in vivo antioxidant activities as lipid peroxidation(LPO), reduced glutathione(GSH).superoxide dismutase(SOD) and calalase(CAT) were screened along with histopathological studies.Results:Obtained results demonstrated that the treatment with SXE significantly(P【0.05- 【0.001) and dose-dcpendcntly prevented chemically induced increase in serum levels of hepatic enzymes.Furthermore.SXE significantly(up to P【0.001) reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH,SOU and catalasc towards normal levels.Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. Conclusions:The results of this study strongly indicate the protective effect of SXE against acute liver injun which may he attributed to its hepatoprotective activity,and there by scientifically support its traditional use. 展开更多
关键词 SOLANUM xanthocarpum HEPATOPROTECTIVE CCL4 Antioxidant ALKALINE phosphatise
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Alpine Ecosystems of Northwest Yunnan,China:an Initial Assessment for Conservation 被引量:4
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作者 Ruth Sherman Renee Mullen +2 位作者 LI Haomin FANG Zhendong WANG Yi 《Journal of Mountain Science》 SCIE CSCD 2007年第3期181-192,共12页
Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the ... Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the world that harbor many unique species that have not been well studied,such as the alpine zone of the Hengduan Mountains of Northwest Yunnan (NWY),a global biodiversity hotspot and site of The Nature Conservancy’s Yunnan Great Rivers Project. We conducted a quantitative,but rapid regional-level assessment of the alpine flora across NWY to provide a broad-based understanding of local and regional patterns of the alpine flora,the first large-scale analysis of alpine biodiversity patterns in this region. Multivariate analyses were used to classify the major plant community types and link community patterns to habitat variables. Our analysis indicated that most species had small distributions and/or small population sizes. Strong patterns emerged with higher diversity in the more northern mountains,but beta diversity was high,averaging only 10% among sites. The ordinations indicated that elevation and geographic location were the dominant environ-mental gradients underlying the differences in the species composition among communities. The high beta diversity across the alpine of these mountains implies that conservation strategies ultimately will require the protection of large numbers of species over a large geographical area. However,prioritiza-tion should be given to areas where potential payoffs are greatest. Sites with high species richness also have a greater number of endemic species,and,by focusing efforts on these sites,conservation investments would be maximized by protecting the greatest number of unique species. 展开更多
关键词 Biodiversity hotspot cluster analysis plant community ecology conservation action GRAZING Hengduan Mountains non-metric multidimensional scaling plant species richness World Heritage Site Yunnan Great Rivers Project(YGRP) alpine ecosystems China
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Early Miocene flora of central Kazakhstan(Turgai Plateau) and its paleoenvironmental implications 被引量:4
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作者 Popova Svetlana Utescher Torsten +3 位作者 Averyanova Anna Tarasevich Valentina Tropina Polina Xing Yaowu 《Plant Diversity》 CAS CSCD 2019年第3期183-197,共15页
The investigation of the fossil floras from the Turgai plateau (central Kazakhstan) contributes to a better understanding of the origin of the temperate Turgai type flora which spread to Kazakhstan and adjacent areas ... The investigation of the fossil floras from the Turgai plateau (central Kazakhstan) contributes to a better understanding of the origin of the temperate Turgai type flora which spread to Kazakhstan and adjacent areas during the Oligocene-Miocene transition. In this paper, we present the results of a carpological and palynological study of the Kumyrtas flora collected from a flora-bearing horizon of the regional coalbearing Zhilanchik suite, dated to the Aquitanian period. Pollen analysis identified 33 taxa, with are dominated by angiosperms (about 73%) and reflect zonal vegetation. The high percentages of Betula (27%) and Pterocarya (7.5%) that were found in this flora allows comparisons with other Aquitanian floras of Kazakhstan. Based on descriptions of fossil fruits and seeds, we determined that 19 taxa were dominant;these taxa had meosphytic herbaceous components, suggesting mostly edaphic local conditions. The incongruence between the carpological and the pollen records suggests a significant taphonomical effect. Quantitative reconstruction of the palaeoclimate based on pollen records supports—and slightly extends—previous findings based on fossil leaf data, but contradicts findings deduced from the carpological record. Plant Functional Type (PFT) classification was used to characterize the vegetation patterns. Pollen records show that about 45% of diversity relates to the arboreal broadleaved deciduous components and ca. 35% to conifers. Fossil fruit and seed data indicate riverine vegetation with a high diversity of aquatic components and shrub stratum. 展开更多
关键词 Kazakhstan Turgai FLORA Oligocenee-Miocene TRANSITION PALAEOCLIMATE reconstruction PFT
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